A. Field of the Invention
The invention relates to a brake lever arm having an adjusting mechanism therein which adjusts the reach of the brake lever arm and the length of the movement of the brake lever arm.
B. Description of the Related Art
At one time, brake actuating mechanisms for bicycles were merely levers coupled to the handle bar of a bicycle with a cable connected to the lever, the opposite end of the cable being connected to a brake mechanism adjacent to one of the bicycle wheels. However, brake mechanisms and brake actuating mechanisms have become very sophisticated in recent years.
Brake actuating mechanisms usually include a lever arm mounted to a base member for pivotal movement. The base member is typically mounted to a handlebar of a bicycle. A cable extends from the brake mechanism to the lever arm. The lever arm pivots between a brake engagement position and a brake disengagement position. In the brake engagement position, the cable is pulled by the lever arm so that the brake mechanism is engaged to stop tire rotation. In the brake disengagement position, the cable tension is released and the brake mechanism is disengaged. Typically, in the brake disengagement position, the lever arm is spaced apart from the handlebar by a predetermined distance. In the brake engagement position, the lever arm is closer to the handlebar than it is in the brake disengagement position.
Until recently, the lever arm on brake actuation mechanisms were manufactured in accordance with a one size fit all approach. A single generic lever arm was expected to be used by all types of bicyclists. However, the needs of individual bicycle users differs from person to person. For instance, some bicyclists have small hands and some have large hands. Those bicyclists with small hands and short fingers have a short reach and therefore may have difficulty keeping the palm of their hands on a bicycle handlebar grip and reaching the lever arm. Conversely, a bicyclist with large hands may find that his fingers wrap too easily around the lever arm and may not have an optimal engagement with the lever arm.
Recently, brake actuation mechanisms have been introduced which include an adjustment mechanism which allows adjustment of the location of the lever arm when the brake mechanism is in a brake disengagement position. The brake disengagement position adjustment is defined as the reach of a lever arm. Such reach adjustment mechanisms at least allow for some user adjustable features enabling a manufacturer to manufacture one component that may be used by a variety of bicyclists.
Such adjustable lever arms have a sever shortcoming in that the stroke of the lever arm is not adjusted accordingly. The stroke of the lever arm is defined as the total distance the lever arm moves from the brake disengagement position to the brake engagement position. The stroke length may be small or large depending on many things such as the brake mechanism used, how well the brake mechanism is adjusted, the length of the cable, to name a few. Adjustable lever arms appear to fail to provide for the lever arm stroke length. For instance, in the case where the stroke is relatively large and the adjustable lever arm is adjusted to accommodate small hands, the lever arm would be adjusted to be closer to the handlebar in the brake disengagement position. After such an adjustment, the lever arm might contact the handlebar before the brake is engaged causing possible ineffective braking.